I purchased the X900E at launch and returned for the KS8500. The Samsung without local dimming has a slightly better static contrast ratio, can get almost 600nit brighter and has 50% lower input lag (unless Sony has managed to update this since.

The Samsung KS8000 /KS8500 (curved) are stellar 4K/HDR displays with 7000:1 native contrast, nearly 1200 nit peak brightness and low input lag. It has been the best TV I have ever owned, but if you want one now is the time to grab it supplies are running low.

Dual layer blu ray displays top out at 50gb, but could in theory cram more data through compression. If you start compressing to much you'll start seeing diminishing returns. Uhd disc triple layer can go up to 100gb triple layer, but the increased cost of the disc would be passed on to developers. Hard drives are faster than the currently employed UHD drive in the XB1S /X,so it makes sense for them to use the HDD.

Of all the things complained about post E3 the size on the One X wasn't on the list. They have been able to cram 4 additional gigs of ram and new SoC with vapor cooling solution at a smaller size than the S.